A prior art method of forming a cord-reinforced tire structural member, such as a belt or a carcass ply, disclosed in, for example, WO 02/055289 forms a tire structural member of a predetermined length by cutting a cord-reinforced band into a plurality of narrow, cord-reinforced strips of a predetermined length and successively connecting the cord-reinforced strips such that the side edge parts of adjacent cord-reinforced strips overlap each other.
The width of the cord-reinforced band is equal to πD/n+α, where D is the diameter of a forming drum, n is an integer and α is the width of the side edge part of the cord-reinforced strip.
The pitch p of the cords of the cord-reinforced band is dependent on the required performance of the tire, such as durability, capability to ensure driving stability and capability to improve ride comfort as well as the strength and elastic modulus of the materials of the tire. The number of the reinforcing cords in the cord-reinforced band is equal to the integral part of {(πD/n)+α}/p.
Practically, the number of the reinforcing cords and the pitch p of the reinforcing cords are parameters of the standard width of the cord-reinforced band. For example, the standard width of a cord-reinforced band in a first example reinforced with twenty-four cords arranged at a pitch p of 1.64 mm is 39.36 mm (=1.64×24 mm) as shown in FIG. 6.
The standard width of a cord-reinforced band in a second example reinforced with seventeen cords arranged at a pitch of 2.27 mm is 38.50 mm (=2.27×17 mm) as shown in FIG. 7.